Alexandre Deur's side hustle, described in the sidebar link, is his work on a gravitational explanation for dark matter and dark energy phenomena, which would solve several of the greatest unsolved problems in physics.
His day job is as a QCD physicist at Jefferson Lab, a U.S. Department of Energy particle physics facility in Newport News, Virginia. There, his progress in determining the value of the least accurately known Standard Model model coupling constant, and confirming that its running with energy scale is consistent with the Standard Model, is also a good thing.
Unsurprisingly, the research done by him and his colleagues confirms that the Standard Model's running of the strong force coupling constant of quantum chromodynamics determined experimentally confirms the Standard Model over a huge range of energy scales (from hundreds of MeVs to about 14,000,000 MeV).
The strong force coupling constant is usually quoted with values converted using the beta-function that describes its running with energy scale in the Standard Model to the Z-boson mass of 91.188 ± 0.002 GeV (according to the Particle Data Group, inverse error weighted world average measurement). Its world average value normalized to that energy scale is 0.1180(9).
The numerical values shown below are in a normalized scale, so the numerical value doesn't match the familiar number.
We discuss how the Bjorken sum rule allows access to the QCD running coupling αs at any scale, including in the deep infrared IR domain. The Bjorken sum data from Jefferson Lab, together with the world data on αs reported by the Particle Data Group, allow us to determine the running of α(s)(Q) over five orders of magnitude in four-momentum Q. We present two possible future measurements of the running of α(s)(Q) using the Bjorken sum rule: the first at the EIC, covering the range 1.5 < Q < 8.7 GeV, and the second at Jefferson Lab at 22 GeV, covering the range 1.0 < Q < 4.7 GeV.
A. Deur, "The strong coupling from the IR to the UV extremes: Determination of α(s) and prospects from EIC and JLab at 22 GeV" arXiv:2510.19556 (October 22, 2025) (Contribution to the proceedings of the "QCD at the Extremes" workshop, Sept. 1-11 2025).
The paper above discusses how proposed low energy experiments at the electron-ion collider at the Brookhaven Lab on Long Island, New York (EIC) and JLab would greatly reduce uncertainties in the measurement of the strong force coupling constant measurement at low energies (i.e. below 5,000 MeV) as shown by the chart below.
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